import { useEffect } from 'react'
import {useState} from 'react'

async function queryData() {
        const data =await new Promise((resolve)=>{
            setTimeout(()=>{
                resolve(666)
            },2000)
        })
        return data
    }


function App(){
    const [num,setNum] = useState(0)
    useEffect(()=>{
        queryData().then(data =>{
            setNum(data)
        })
    },[])

    return (
        <div onClick={() =>{
            setNum((preNum)=> preNum +1)
        }}>{num}</div>
    )
}
export default App
